EP0502819A1 - Acid hardenable copolymers - Google Patents

Abstract

The invention relates to copolymers which can be crosslinked by acid catalysis and have a molecular weight (Mw) of from 10<3> to 10<6>, measured by gel permeation chromatography, and which comprise   a) 100-80 mol % of recurring structural units of the formulae I and II <IMAGE> and <IMAGE> in a ratio of from 1:1 to 1:9 and   b) 0.20 mol % of recurring structural units of the formula III <IMAGE> in which   X and X', independently of one another, are <IMAGE>   R is hydrogen or a protecting group which can be removed by means of acid,   the R1 radicals independently of one another, are C1-C5-alkyl, phenyl or naphthyl or together are 1,2-phenylene or -[C(R3)(R4)]x- where R3 and/or R4 are hydrogen or methyl and x is 2 to 5,   the R2 radicals, independently of one another, are hydrogen, C1-C5-alkyl or C1-C5-alkoxy.   R5 and R7 are each hydrogen,   R6 is hydrogen, halogen or methyl, and   R8 is hydrogen, halogen, methyl, -CH2 halogen, -CH2CN, -CN, -COOH, -CONH2, -O-C1-C5-alkyl, -O-CO-C1-C5-alkyl, -COO-C1-C5-alkyl, -COO-phenyl or phenyl,   or R5 and R6 are each hydrogen and R7 and R8 together are -CO-O-CO- or, independently of one another, are -COOH or -COO-C1-C5-alkyl. <??>Together with compounds which form an acid when exposed to actinic radiation, said copolymers are suitable for the production of negative resist systems.

Description

The present invention relates to acid-catalytically crosslinkable copolymers of acetalized and OH group-containing vinylbenzenes or N-phenylmaleimides, such copolymers and radiation-sensitive compositions containing an acid-forming substance and their use as a negative resist for the production of protective layers and relief structures.

Negative resist compositions working on the principle of so-called chemical amplification are known from the literature. JMF Fréchet et al. in polym. Mat. Sci. Eng., 60 (1989) 147-150, in Macromolecules, 24 (1991) 1746-1754 or in Polymer Engineering and Science, 29 No. 14 (July 1989) 960-964 negative resists of the amplification type based on electrophilic aromatic substitution. Here, copolymers are prepared from 4-t-butyloxycarbonylstyrene and 4-acetyloxymethylstyrene and, after the t-butyloxycarbonyl protective groups have been split off, these are irradiated with UV light at 254 nm in the presence of a triarylsulfonium salt as acid generator, such as triphenylsulfonium hexafluoroantimonate, with the irradiated sites will. Instead of the mixtures of copolymer and acid-generating triarylsulfonium salt mentioned, it is also possible to use 3-component systems composed of multifunctional low molecular weight latent electrophiles, such as 1,4-bis (acetyloxymethyl) benzene, triarylsulfonium salt and a phenolic polymer. Similar negative resist systems based on onium salts, a polyfunctional compound with activated aromatic rings and a polyfunctional compound providing carbonium ions, at least one of these two compounds being a polymer or copolymer, are described in US Pat. No. 4,800,152. M Hatzakis et al. describe in Microelectronic Engineering, 11 (1990) 487-490 negative resist compositions based on epoxidized novolaks and onium salts as acid-generating substances. The latter systems cannot be developed in an aqueous-alkaline manner.

On the other hand, it is known that acid-cleavable monomeric or polymeric acetals and ketals together with photoactivatable acid-forming compounds and optionally binders are suitable for producing positive-working photoresist systems (see, for example, DE-A 2718 254, US Pat. No. 3,779,778 and EP-A 0 202196).

It has now been found that certain copolymers of acetalized and OH group-containing vinyl benzenes or N-phenylmaleimides are surprisingly suitable for the production of negative resist systems based on the principle of chemical amplification.

• a) 100-80 Mol.%o wiederkehrender Strukturelemente der Formeln I und II
  
  im Verhältnis von 1:1 bis 1:9, bevorzugt 1:2 bis 1:4, und
• b) 0-20 Mol.% wiederkehrender Strukturelemente der Formel III
  
  bestehen, worin
  X und X′ unabhängig voneinander
  
  bedeuten,
  R Wasserstoff oder eine unter Säureeinwirkung abspaltbare Schutzgruppe ist, die R₁ unabhängig voneinander C₁-C₅-Alkyl, Phenyl oder Naphthyl bedeuten oder zusammen 1,2-Phenylen oder -[C(R₃)(R₄)]_x- mit R₃ und/oder R₄ = Wasserstoff oder Methyl und x = 2 bis 5, besonders 2 bis 4, darstellen,
  die R₂ unabhängig voneinander Wasserstoff, C₁-C₅-Alkyl oder C₁-C₅-Alkoxy darstellen,
  R₅ und R₇ je Wasserstoff sind,
  R₆ Wasserstoff, Halogen oder Methyl und
  R₈ Wasserstoff, Halogen, Methyl, -CH₂Halogen, -CN, -CH₂CN, -COOH, -CONH₂, -O-C₁-C₅-Alkyl, -O-CO-C₁-C₅-Alkyl, -COO-C₁-C₅-Alkyl, -COO-Phenyl oder Phenyl bedeuten,
  oder R₅ und R₆ je Wasserstoff sind und R₇ und R₈ zusammen -CO-O-CO- oder unabhängig voneinander -COOH oder -COO-C₁-C₅-Alkyl darstellen.

The invention therefore relates to acid-catalytically crosslinkable copolymers with a molecular weight (Mw) of 10³ to 10⁶, measured by means of gel permeation chromatography, from

• a) 100-80 mol.% o recurring structural elements of the formulas I and II
  
  in a ratio of 1: 1 to 1: 9, preferably 1: 2 to 1: 4, and
• b) 0-20 mol% of recurring structural elements of the formula III
  
  consist in what
  X and X 'independently of each other
  
  mean,
  R is hydrogen or a protective group which can be split off under the action of an acid and which R₁ independently of one another is C₁-C₅-alkyl, phenyl or naphthyl or together 1,2-phenylene or - [C (R₃) (R₄)] _x - with R₃ and / or R₄ = hydrogen or methyl and x = 2 to 5, especially 2 to 4,
  the R₂ are independently hydrogen, C₁-C₅-alkyl or C₁-C₅-alkoxy,
  R₅ and R₇ are each hydrogen,
  R₆ is hydrogen, halogen or methyl and
  R₈ is hydrogen, halogen, methyl, -CH₂Halogen, -CN, -CH₂CN, -COOH, -CONH₂, -O-C₁-C₅-alkyl, -O-CO-C₁-C₅-alkyl, -COO-C₁-C₅-alkyl , -COO-phenyl or phenyl,
  or R₅ and R₆ are each hydrogen and R₇ and R₈ together represent -CO-O-CO- or independently of one another -COOH or -COO-C₁-C₅-alkyl.

The copolymers according to the invention preferably have a molecular weight (Mw) of 5,000 to 500,000, in particular 5,000 to 20,000.

Furthermore, copolymers are preferred in which the proportion of recurring structural elements of the formulas I and II is 100 to 90 mol% and that of structural elements of the formula III is 0-10 mol%.

und insbesondere je

dar.X and X 'are preferred

and especially ever

represents.

-CO-R₁₃ (VII) genannt, worin
R₉ Wasserstoff oder Methyl ist,
R₁₀ C₁-C₅-Alkyl, Phenyl oder Naphthyl bedeutet und R₁₁ und R₁₂ unabhängig voneinander Wasserstoff, C₁-C₅-Alkyl, Phenyl oder Naphthyl sind, oder
R₁₀ und R₁₂ zusammen unsubstituiertes oder durch C₁-C₄-Alkyl, C₁-C₄-Alkoxy, Phenyl, Naphthyl, Phenoxy oder Naphthyloxy substituiertes Ethylen, Propylen oder Butylen darstellen,
y für 2, 3 oder 4 steht, und
R₁₃ C₁-C₅-Alkyl oder C₁-C₅-Alkoxy bedeutet.Examples of protective groups R which can be removed under the action of acid are residues of the formulas IV-VII

-CO-R₁₃ (VII) called, wherein
R₉ is hydrogen or methyl,
R₁₀ is C₁-C₅-alkyl, phenyl or naphthyl and R₁₁ and R₁₂ are independently hydrogen, C₁-C₅-alkyl, phenyl or naphthyl, or
R₁₀ and R₁₂ together represent unsubstituted or substituted by C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, naphthyl, phenoxy or naphthyloxy, ethylene, propylene or butylene,
y represents 2, 3 or 4, and
R₁₃ is C₁-C₅ alkyl or C₁-C₅ alkoxy.

Alkyl groups represented by R₁, R₂, R₁₀, R₁₁, R₁₂ or R₁₃ or contained in radicals R₈, R₁₀ and R₁₂ and alkoxy groups R₂ and R₁₃ or in radicals R₁ R or R₁₂ may be straight-chain or branched. Examples include: methyl, ethyl, n-propyl, isopropyl, n-, sec- and tert-butyl, n-pentyl, methoxy, ethoxy, n-propoxy, isopropyloxy, n- and tert-butyloxy, n-pentyloxy.

R₁, R₂, R₁₀, R₁₁ and R₁₂ as alkyl or alkoxy are in particular methyl, ethyl, methoxy or ethoxy, especially methyl or methoxy. Halogen in groups R₆ and Rg is e.g. Cl, Br or F.

The two R₁ are preferably - [C (R₃) (R₄)] _x - with x = 2 to 4, in particular 2 or 3. The R₂ are preferably hydrogen.

In preferred radicals of the formula IV, R₉ has the meaning given, R₁₀ is methyl or ethyl, R₁₁ and R₁₂ independently of one another are hydrogen or methyl or R₁₀ and R₁₂ together represent unsubstituted ethylene or propylene. y in radicals of formula V is preferably 2 or 3, and in radicals of formula VII R₁₃ represents in particular C₁-C₅ alkoxy, especially tert-butyloxy.

R is preferably hydrogen or -COO-C (CH₃) ₃ and especially a radical of formula V with y = 2 and in particular 3. R is particularly preferably hydrogen.

im Verhältnis von 1:1 bis 1:9 und
0-20 Mol.% einer Verbindung der Formel IIIa.

worin R, R₁, R₂ und R₅ bis R₈ die oben angegebene Bedeutung haben und X˝

bedeutet, und gegebenenfalls säurekatalysiertes Abspalten der Schutzgruppe R, hergestellt werden.The copolymers according to the invention can be prepared in a manner known per se by radical copolymerization of 100-80 mol% of compounds of the formulas Ia and IIa

in the ratio of 1: 1 to 1: 9 and
0-20 mol% of a compound of formula IIIa.

wherein R, R₁, R₂ and R₅ to R₈ have the meaning given above and X˝

means, and optionally acid-catalyzed removal of the protective group R, are prepared.

It is often advantageous to use compounds of the formula IIa, in which R is a protective group which can be split off under the action of acid, for the copolymerization. It is also not necessary to remove the protective group R before the copolymers according to the invention are used in negative resist systems. This removal is preferably carried out in the presence of a compound which forms an acid under actinic radiation.

The radical copolymerization can be carried out using various techniques. These have been described, for example, by S. Sandler and W. Karo in "Polymer Synthesis", Vol. 1-3, 1968, Academic Press, New York. Typical polymerization processes are, for example, bulk or solvent polymerization, emulsion, suspension or precipitation polymerization.

The starting products of formula Ia are known or can be prepared by methods known per se, for example by reacting the corresponding benzaldehydes with catechol, mono- or dihydroxy compounds R₁OH or HO- [C (R₃) (R₄)] _x -OH.

und Q-CO-R₁₃ (VIIa),
worin Q eine reaktionsfähige Gruppe, z.B. -Cl, darstellt, erhalten werden.Most of the compounds of the formula IIa with R = H are known or can be prepared by processes known per se. Compounds of the formula IIa, in which R represents a protective group by definition, can be reacted with compounds of the formulas IVa to VIIa by reacting the corresponding compounds of the formula IIa with R = H

and Q-CO-R₁₃ (VIIa),
wherein Q represents a reactive group, eg -Cl, are obtained.

The compounds of formula IIIa are also known and some of them are commercially available. Examples of monomers of formula IIIa are ethylene, propylene, styrene, α-methylstyrene, acrylonitrile, α, β-unsaturated acids and amides, such as e.g. Acrylic acid, acrylic acid methyl ester and acrylic acid amide and the corresponding methacrylic compounds, maleic acid, maleic acid methyl ester, maleic acid dimethyl and diethyl ester, halogen-containing vinyl compounds, e.g. Vinyl chloride, vinyl fluoride, vinylidene chloride or vinylidene fluoride, vinyl esters and vinyl ethers such as e.g. Vinyl acetate, methyl vinyl ether and butyl vinyl ether. Other suitable connections are e.g. Allyl bromide, allyl chloride and allyl cyanide.

The polymerization is generally initiated by one of the usual free-radical polymerization initiators. These include thermal initiators, such as azo compounds, for example α, α′-azoisobutyronitrile (AIBN), or peroxides, for example benzoyl peroxide, or redox initiator systems, such as a mixture of iron (III) acetyl acetonate, benzoin and benzoyl peroxide, or photochemical radical formers, such as benzoin or benzil dimethyl ketal.

The polymerization is preferably carried out in solution. The reaction temperature is generally in the range from 10 to 200 ° C., preferably between 40 and 150 ° C., particularly preferably between 40 and 100 ° C.

Any solvents present must be inert under the reaction conditions. The solvents used include aromatic hydrocarbons, chlorinated hydrocarbons, ketones and ethers. Examples include: benzene, toluene, xylenes, ethylbenzene, isopropylbenzene, ethylene chloride, propylene chloride, methylene chloride, chloroform, methyl ethyl ketone, acetone, cyclohexanone, diethyl ether or tetrahydrofuran.

The copolymers according to the invention are suitable for the production of highly sensitive negative-resist compositions which can be developed in aqueous-alkaline form.

• i) mindestens ein definitionsgemässes Copolymer und
• ii) mindestens eine unter aktinischer Strahlung säurebildende Verbindung.

The invention therefore also relates to radiation-sensitive compositions

• i) at least one copolymer by definition and
• ii) at least one acid-forming compound under actinic radiation.

The acid formed in the irradiated areas catalyzes the crosslinking of the copolymer, with any protective groups R being removed. Preferred copolymers i) are explained in the foregoing.

As acid-forming compounds under actinic radiation come e.g. considered:

worin
Ar₁ unsubstituiertes oder durch Halogen, C₁-C₄-Alkyl, C₁-C₄-Alkoxy, -OH und/oder Nitro substituiertes Phenyl, Naphthyl oder Phenyl-COCH₂- ist,
Z₁ C₁-C₆-Alkyl oder C₃-C₇-Cycloalkyl und
Z₂ Tetrahydrothienyl, Tetrahydrofuryl oder Hexahydropyryl sind,
q für 0, 1, 2 oder 3,
r für 0, 1 oder 2 und
s für 0 oder 1 stehen, wobei die Summe q+r+s 3 beträgt, und
X₁^⊖ ein Chlorid-, Bromid- oder Iodidanion, BFq^⊖, PF₆^⊖, AsF₆^⊖, SbF₆^⊖, FSO^⊖ oder das Anion einer organischen Sulfonsäure oder Carbonsäure ist.Particularly suitable compounds ii) which form acid under actinic radiation are onium salts, such as diazonium, sulfonium, sulfoxonium and iodonium salts. Sulfonium salts of the formula VIII are preferred $${\text{(Ar₁)}}_{\text{q}}{\text{(Z₁)}}_{\text{r}}{\text{(Z₂)}}_{\text{s}}{\text{S}}^{\text{⊕}}{\text{X₁}}^{\text{⊖}}$$

wherein
Ar₁ is phenyl, naphthyl or phenyl-COCH₂- which is unsubstituted or substituted by halogen, C₁-C₄-alkyl, C₁-C₄-alkoxy, -OH and / or nitro,
Z₁ C₁-C₆-alkyl or C₃-C₇-cycloalkyl and
Z₂ are tetrahydrothienyl, tetrahydrofuryl or hexahydropyryl,
q for 0, 1, 2 or 3,
r for 0, 1 or 2 and
s stand for 0 or 1, the sum q + r + s being 3, and
X₁ ^{⊖ is} a chloride, bromide or iodide anion, BFq ^⊖ , PF₆ ^⊖ , AsF₆ ^⊖ , SbF₆ ^⊖ , FSO ^⊖ or the anion of an organic sulfonic acid or carboxylic acid.

Phenyl, naphthyl and phenacyl groups Ar 1 are preferably simply substituted, in particular by Cl, Br, methyl, methoxy, -OH or nitro. These radicals are particularly preferably unsubstituted. Z₁ is preferably C₁-C₄ alkyl, especially methyl or ethyl. Q 2 or 3, r 1 or zero and s are preferably zero, in particular q = 3 and r and s are zero. Ar 1 is very particularly preferably unsubstituted phenyl and q is 3.

X₁ ^{⊖ represents} the anion of an organic sulfonic acid or carboxylic acid, it can be anions of aliphatic, cycloaliphatic, carbocyclic-aromatic, heterocyclic-aromatic or araliphatic sulfonic or carboxylic acids. These anions can be substituted or unsubstituted. Preferred are sulfonic and carboxylic acids with low nucleophilicity, for example partially or perfluorinated derivatives or derivatives substituted in the vicinity of the respective acid group. Examples of substituents are halogen, such as chlorine or especially fluorine, alkyl, such as methyl, ethyl or n-propyl, or alkoxy, such as methoxy, ethoxy or n-propoxy.

Examples of aliphatic sulfonic acids are methane, ethane, n-propane, n-butane and n-hexanesulfonic acid or the corresponding partially or perfluorinated derivatives.

Examples of aliphatic carboxylic acids are formic acid, acetic acid, propionic acid, butyric acid, pivalic acid, caproic acid, 2-ethylhexylcarboxylic acid and fatty acids, such as lauric acid, myristic acid or stearic acid, and the partially or perfluorinated derivatives of these acids.

Examples of cycloaliphatic sulfonic or carboxylic acids are cyclohexanesulfonic acid, cyclohexane carboxylic acid, camphor-10-sulfonic acid or their partially or perfluorinated derivatives.

Examples of carbocyclic aromatic sulfonic acids are benzene, toluene, ethylbenzene, isopropylbenzene, dodecylbenzene or dimethylbenzenesulfonic acid, 2,4,6-triisopropylbenzenesulfonic acid, 2,4,6-trimethylbenzenesulfonic acid, naphthalene mono-, di- or - tri-sulfonic acids and the corresponding alkylated or partially or perfluorinated derivatives of these sulfonic acids.

Examples of heterocyclic aromatic sulfonic acids are pyridine, thiophene or pyrrole sulfonic acid and the corresponding partially or perfluorinated derivatives of these acids.

Examples of araliphatic sulfonic acids are benzyl sulfonic acid, α-methylbenzyl sulfonic acid and the corresponding partially or perfluorinated derivatives of these compounds.

Examples of carbocyclic aromatic carboxylic acids are benzoic acid, toluene, ethylbenzene, isopropylbenzene or dimethylbenzene carboxylic acid, naphthalene carboxylic acid or anthracenecarboxylic acid and the corresponding partially or perfluorinated derivatives of these compounds.

Examples of heterocyclic aromatic carboxylic acids are pyridine, thiophene or pyrrole carboxylic acid and the corresponding partially or perfluorinated derivatives of these compounds.

Examples of araliphatic carboxylic acids are benzyl carboxylic acid, α-methylbenzyl carboxylic acid and cinnamic acid, and the corresponding partially or perfluorinated derivatives of these compounds.

X₁ ^{⊖ is preferably} the monovalent anion of an organic sulfonic acid, in particular a partial fluorine or perfluorosulfonic acid. These anions are characterized by a particularly low nucleophilicity.

VIII Specific examples of suitable sulfonium salts of the formula triphenylsulfonium bromide, triphenylsulfonium chloride, triphenylsulfonium iodide, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, Triphenylsulfonium hexafluoroarsenate, triphenylsulfonium trifluoromethanesulfonate, Diphenylethylsulfoniumchlorid, Phenacyldimethylsulfoniumchlorid, Phenacyltetrahydrothiopheniumchlorid, 4-Nitrophenacyltetrahydrothiopheniumchlorid and 4-hydroxy-2-methylphenylhexahydrothiopyryliumchlorid. Triphenylsulfonium trifluoromethanesulfonate is particularly preferred.

verwendet werden, worin
Ar₂ und Ar₃ unabhängig voneinander unsubstituiertes oder durch C₁-C₄-Alkyl, C₁-C₄-Alkoxy, Halogen und/oder Nitro substituiertes Phenyl oder Naphthyl sind oder Ar₂ oder Ar₃ zusammen eine Gruppe der Formel X

darstellen, worin Z₃ C₁-C₄-Alkyl, C₁-C₄-Alkoxy, Halogen oder Nitro und Y eine Direktbindung, -O-, -CH₂- oder -CO- darstellen und X₂^⊖ ein Chlorid-, Bromid- oder Iodidanion bedeutet. Iodoniumsalze der Formel IX sind z.B. in der GB-A 1539 192 beschrieben.Iodonium salts of the formula IX $${\text{[Ar₂-I}}^{\text{⊕}}{\text{-Ar₃] X₂}}^{\text{⊖}}$$

be used in which
Ar₂ and Ar₃ are independently phenyl or naphthyl which is unsubstituted or substituted by C₁-C₄-alkyl, C₁-C₄-alkoxy, halogen and / or nitro, or Ar₂ or Ar₃ together are a group of the formula X.

represent where Z₃ is C₁-C₄ alkyl, C₁-C₄ alkoxy, halogen or nitro and Y is a Direct bond, -O-, -CH₂- or -CO- represent and X₂ ^{⊖ is} a chloride, bromide or iodide anion. Iodonium salts of the formula IX are described, for example, in GB-A 1539 192.

worin
t 1 oder 2, bevorzugt 1 ist,
Z₄ unsubstituiertes oder durch 1-3 -Cl, -Br, -CN, -NO₂, C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄-Alkylthio, Phenoxy, Phenylthio, C₁-C₄-Alkylamino, C₂-C₄-Dialkylamino oder Benzoyl substituiertes Phenyl oder Naphthyl, besonders unsubstituiertes oder einfach durch -Cl, Methyl oder Methoxy substituiertes Phenyl darstellt,
Z₅ Wasserstoff oder C₁-C₄-Alkyl und
Z₆ Wasserstoff, C₁-C₄-Alkyl oder Phenyl bedeuten oder
Z₅ und Z₆ zusammen mit dem Bindungs-C-Atom einen Cyclopentan- oder Cyclohexanring bilden,
Z₇, bei t = 1, C₁-C₈-Alkyl, unsubstituiertes oder durch C₁-C₄-Alkyl substituiertes Phenyl oder Naphthyl, Cyclopentyl, Cyclohexyl oder Campheryl und bei t = 2 C₂-C₈-Alkylen oder Phenylen bedeutet,
Z₈ unsubstituiertes oder durch 1-3 -Cl, -Br, C₁-C₄-Alkyl, C₁-C₄-Alkoxy, C₁-C₄-Alkylthio, Phenyl, Phenoxy, Phenylthio, C₁-C₄-Alkyl-CONH-, Benzoylamino, Dimethylamino substituiertes Phenyl oder Naphthyl, besonders unsubstituiertes oder einfach durch -Cl, C₁-C₄-Alkoxy, Methylthio oder Phenyl substituiertes Phenyl ist,
Z₉ -OH oder C₁-C₄-Alkyl ist,
Z₁₀ C₁-C₄-Alkyl oder Phenyl ist,
Z₁₁ Wasserstoff, C₁-C₄-Alkyl, Furyl oder -CCl₃ bedeutet oder
Z₁₀ und Z₁₁ zusammen mit dem Bindungs-C-Atom einen Cyclopentan- oder Cyclohexanring bilden,
Z₁₂ und Z₁₃ unabhängig voneinander unsubstituiertes oder durch Halogen, C₁-C₄-Alkyl oder C₁-C₄-Alkoxy substituiertes Phenyl sind,
Z₁₄ Wasserstoff oder C₁-C₄-Alkyl darstellt,
Z₁₅ bei t = 1, C₁-C₆-Alkyl, Phenyl, Naphthyl oder Benzyl und bei t 2 C₁-C₆-Alkylen, Phenylen oder Xylylen darstellt,
Z₁₆ unsubstituiertes oder durch Halogen, Nitro, C₁-C₄-Alkyl, C₁-C₄-Alkoxy oder C₁-C₄-Alkylthio substituiertes Phenylen oder Naphthylen oder -CH=CH- ist, Z₁₇ bei t = 1 C₁-C₁₂-Alkyl, unsubstituiertes oder durch Halogen, Nitro, C₁-C₄-Alkyl oder C₁-C₄-Alkoxy substituiertes Phenyl und bei t = 2 C₂-C₈-Alkylen oder Phenylen ist,
Z₁₈ unsubstituiertes oder durch Halogen, Nitro, -CN, C₁-C₄-Alkyl, Methoxy, Ethoxy, Dimethylamino oder Benzoyl substituiertes Phenyl oder Naphthyl bedeutet und die Z₁₉ unabhängig voneinander C₁-C₄-Alkyl sind.Also suitable as compounds ii) are substances of the formulas XI to XVII which generate sulfonic acid under actinic radiation

wherein
t is 1 or 2, preferably 1,
Z₄ unsubstituted or by 1-3 -Cl, -Br, -CN, -NO₂, C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkylthio, phenoxy, phenylthio, C₁-C₄-alkylamino, C₂-C₄ Represents dialkylamino or benzoyl-substituted phenyl or naphthyl, particularly unsubstituted or simply substituted by -Cl, methyl or methoxy-phenyl,
Z₅ is hydrogen or C₁-C₄ alkyl and
Z₆ is hydrogen, C₁-C₄ alkyl or phenyl or
Z₅ and Z₆ together with the bonding carbon atom form a cyclopentane or cyclohexane ring,
Z₇, at t = 1, C₁-C₈-alkyl, unsubstituted or substituted by C₁-C₄-alkyl phenyl or naphthyl, cyclopentyl, cyclohexyl or camphoryl and at t = 2 C₂-C₈-alkylene or phenylene,
Z₈ unsubstituted or substituted by 1-3 -Cl, -Br, C₁-C₄-alkyl, C₁-C₄-alkoxy, C₁-C₄-alkylthio, phenyl, phenoxy, phenylthio, C₁-C₄-alkyl-CONH-, benzoylamino, dimethylamino Is phenyl or naphthyl, especially unsubstituted or simply substituted by -Cl, C₁-C₄-alkoxy, methylthio or phenyl,
Z₉ is -OH or C₁-C₄-alkyl,
Z₁₀ is C₁-C₄ alkyl or phenyl,
Z₁₁ is hydrogen, C₁-C₄-alkyl, furyl or -CCl₃ or
Z₁₀ and Z₁₁ together with the bond carbon atom form a cyclopentane or cyclohexane ring,
Z₁₂ and Z₁₃ are independently unsubstituted or substituted by halogen, C₁-C₄-alkyl or C₁-C₄-alkoxy,
Z₁₄ represents hydrogen or C₁-C₄ alkyl,
Z₁₅ at t = 1, C₁-C₆-alkyl, phenyl, naphthyl or benzyl and at t 2 C₁-C₆-alkylene, phenylene or xylylene,
Z₁₆ is unsubstituted or substituted by halogen, nitro, C₁-C₄-alkyl, C₁-C₄-alkoxy or C₁-C₄-alkylthio or phenylene or naphthylene or -CH = CH-, Z₁₇ at t = 1 C₁-C₁₂-alkyl, unsubstituted or is phenyl substituted by halogen, nitro, C₁-C₄-alkyl or C₁-C Alk-alkoxy and at t = 2 is C₂-C₈-alkylene or phenylene,
Z₁₈ is phenyl or naphthyl which is unsubstituted or substituted by halogen, nitro, -CN, C₁-C₄-alkyl, methoxy, ethoxy, dimethylamino or benzoyl and the Z₁₉ are independently C₁-C₁-alkyl.

By definition, alkyl, alkoxy, alkylthio, alkylamino, dialkylamino, alkylcarbamoyl and alkylene groups can be straight-chain or branched, but are preferably straight-chain. Halogen means in particular -Cl or -Br.

Compounds of formula XI to XVI are e.g. in EP-A 0166 682 and 0 085 024 and the literature cited therein. Particularly preferred compounds of the formulas XI to XVI are phenacyl p-methylbenzenesulfonate, benzoin p-toluenesulfonate, 3- (p-toluenesulfonyloxy) -2-hydroxy-2-phenyl-1-phenyl-1-propanone [α- (p- Toluenesulfonyloxy) methylbenzoin], N- (p-dodecylbenzenesulfonyloxy) -1,8-naphthalimide and N- (phenylsulfonyloxy) -1,8-naphthalimide.

Further suitable compounds ii) are o-nitrobenzaldehydes which rearrange themselves under actinic radiation in o-nitrosobenzoic acids, such as 1-nitrobenzaldehyde and 2,6-dinitrobenzaldehyde; α-haloacylphenones, such as α, α, α-trichloroacetophenone and p-tert-butyl-α, α, α, trichloroacetophenone, and sulfonic acid esters of o-hydroxyacylphenones, such as 2-hydroxybenzophenone methanesulfonate and 2,4-hydroxybenzophenone bis (methanesulfonate) .

mit mindestens einem aromatisch gebundenen Chlor- oder Bromatom, worin z.B. p 0 oder 1 bedeutet,
Z₂₀ -COOH, -OZ₂₃ oder -SZ₂₃ ist,
Z₂₁ und Z₂₂ unabhängig voneinander Wasserstoff, -Cl, -Br, gegebenenfalls durch Aryl, Alkoxy, Aryloxy, -OH oder -F substituiertes Alkyl oder gegebenenfalls durch Alkoxy, Aryloxy, -OH oder Halogen substituiertes Aryl sind,
Z₂₃ Wasserstoff, gegebenenfalls analog Z₂₁ substituiertes Alkyl oder Aryl oder Acyl ist,
A bei p =0, Wasserstoff, -Cl, -Br, gegebenenfalls analog zu Z₂₁ substituiertes Alkyl und bei p = 1, -SO₂-, Propylen oder Perfluorallcylen ist und B eine Gruppe

Alkylcarbonyl, Alkoxycarbonyl oder substituiertes Sulfonylimidocarbonyl bedeutet. Beispiele derartiger Verbindungen sind Hexafluortetrabrom-Bisphenol A,1,1,1-Tris(3,5-dibrom-4-hydroxyphenyl)ethan und N-(2,4,6-Tribromphenyl)-N′-(p-toluolsulfonyl)harnstoff.Finally, suitable compounds ii) are also those which contain aromatically bound chlorine or bromine, as described, for example, in EP-A 0 318 649, for example compounds of the formula XVIII

with at least one aromatically bound chlorine or bromine atom, in which, for example, p is 0 or 1,
Z₂₀ is -COOH, -OZ₂₃ or -SZ₂₃,
Z₂₁ and Z₂₂ are independently hydrogen, -Cl, -Br, optionally substituted by aryl, alkoxy, aryloxy, -OH or -F alkyl or optionally substituted by alkoxy, aryloxy, -OH or halogen,
Z₂₃ is hydrogen, optionally substituted analogously to Z₂₁ alkyl or aryl or acyl,
A at p = 0, hydrogen, -Cl, -Br, optionally substituted analogously to Z₂₁ alkyl and at p = 1, -SO₂-, propylene or perfluoroallcylene and B is a group

Alkylcarbonyl, alkoxycarbonyl or substituted sulfonylimidocarbonyl means. Examples of such compounds are hexafluorotetrabromo-bisphenol A, 1,1,1-tris (3,5-dibromo-4-hydroxyphenyl) ethane and N- (2,4,6-tribromophenyl) -N '- (p-toluenesulfonyl) urea .

Particularly preferred compounds ii) are those of the formula VIII in which Ar₁ is phenyl, q is 3, r and s are zero, and X₁ SbF₆ ^⊖ , AsF₆ ^⊖ , PF₆ ^⊖ and in particular the anion of an aliphatic, partially fluoroaliphatic or perfluoroaliphatic Sulfonic acid or an aromatic, partially fluorinated or perfluoroaromatic sulfonic acid.
Particularly preferred anions X₁ ^⊖ are CF₃SO₃ ^⊖ , C₂F₅SO₃ ^⊖ , n-C₃F₇SO₃ ^⊖ , C₄F₉SO₃ ^⊖ , n-C₆F₁₃SO₃ ^⊖ , n-C₈F₁₇SO₃ ^⊖ and C₆F₅SO₃ ^⊖ . Very particularly preferably times used as compound ii) triphenylsulfonium trifluoromethanesulfonate.

The compounds ii) are advantageously used in an amount of 0.1 to 20% by weight, particularly 1 to 10% by weight and very particularly 1 to 6% by weight, based on the weight of the copolymer.

The compositions according to the invention can contain further conventional additives, such as e.g. Binders, stabilizers, pigments, dyes, fillers, adhesion promoters, leveling agents, wetting agents and plasticizers. The compositions for application are preferably dissolved in suitable solvents [component iii)].

The choice of binder depends on the area of application and the properties required for this. Suitable binders are, for example, novolaks which are derived from an aldehyde, preferably formaldehyde, acetaldehyde or furfuraldehyde, but especially from formaldehyde, and a phenol. The phenolic component of these binders is preferably phenol itself, or halogenated phenol, for example substituted with one to two chlorine atoms, preferably. p-chlorophenol, or it is a phenol substituted by one to two C₁-C₉-alkyl groups, for example o-, m- or p-cresol, a xylenol, p-tert-butylphenol or p-nonylphenol. However, the phenocomponent of the preferred novolaks can also be p-phenylphenol, resorcinol, bis (4-hydroxyphenyl) methane or 2,2-bis (4-hydroxyphenyl) propane.

Other suitable binders are, for example, copolymers of maleic anhydride with styrene, vinyl ether or 1-alkenes. Homo- or copolymeric acrylates and methacrylates, e.g. Copolymers of methyl methacrylate / ethyl acrylate / methacrylic acid, poly (methacrylic acid alkyl ester) or poly (acrylic acid alkyl ester) with e.g. 1-20 C atoms in the alkyl radical can also be used as binders.

An alkali-soluble substance is preferably used as the binder, for example a novolak (optionally modified as described above), poly (4-hydroxystyrene) or poly (4-hydroxy-3,5-dimethylstyrene), copolymers of maleic anhydride with styrene, vinyl ether or 1- Alkenes, and copolymers of acrylic or methacrylic acid esters with ethylenically unsaturated acids, for example methacrylic acid or acrylic acid.

The radiation-sensitive compositions according to the invention dissolved in a solvent or solvent mixture are outstandingly suitable as coating agents for substrates of all kinds, e.g. Wood, textiles, paper, ceramics, glass, plastics, such as polyester, polyethylene terephthalate, polyolefins or cellulose acetate, in particular in the form of films, and metals, such as Al, Cu, Ni, Fe, Zn, Mg or Co, and GaAs, Si or SiO₂, on which an image is to be applied by imagewise exposure.

The choice of solvent and the concentration depend mainly on the type of composition and the coating process. The solvent should be inert, ie there should be no chemical reaction with the components and it should be possible to remove it again after drying after coating. Suitable solvents are, for example, ketones, ethers and esters, such as methyl ethyl ketone, isobutyl methyl ketone, cyclopentanone, cyclohexanone, N-methylpyrrolidone, dioxane, tetrahydrofuran, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, 1,2-dimethoxyethane, ethyl acetate , N-butyl acetate and ethyl 3-ethoxy-propionate.

The solution is applied uniformly to a substrate, e.g. by spinning, dipping, knife coating, curtain casting, brushing, spraying, especially by electrostatic spraying and reverse roll coating. It is also possible to apply the light-sensitive layer to a temporary, flexible support and then to transfer the final substrate, e.g. a copper-clad printed circuit board.

The application quantity (layer thickness) and the type of substrate (layer carrier) depend on the desired application area. The layer thickness range generally includes values from approx. 0.1 µm to more than 10 µm.

The radiation-sensitive compositions according to the invention are used as a negative resist, which have a very high sensitivity to light and can be developed without swelling in an aqueous alkaline medium. They are suitable as photoresists for electronics (galvanoresist, etching resist, solder resist), the production of printing plates, such as offset printing plates or screen printing forms, the use in molded part etching or the use as micro-resist in the production of integrated circuits. The possible layer supports and the processing conditions of the coated substrates are correspondingly different.

For photographic information records e.g. Foils made of polyester, cellulose acetate or paper coated with plastic; Specially treated aluminum for offset printing forms, copper-clad laminates for the production of printed circuits and silicon wafers for the production of integrated circuits. The layer thicknesses for photographic materials and offset printing forms are generally approx. 0.5 µm to 10 µm, for printed circuits 0.4 to approx. 2 µm.

With the compositions according to the invention, high-resolution relief structures of negative tonality can be produced. Thanks to the high sensitivity and the high optical transparency or the low optical absorption in the UV range around 250 nm, they are particularly suitable for applications in microlithography, especially deep UV microlithography. Thanks to these properties, very steep wall profiles and the resolution of submicron structures (down to 0.5 µm) can be achieved. Such submicron structures cannot be produced, for example, with corresponding compositions containing an acetoxymethyl function in the copolymer molecule. After the substrates have been coated, the solvent is generally removed by drying, and a layer of the photoresist on the support results.

The term “image-wise” exposure includes both exposure through a photomask that contains a predetermined pattern, for example a slide, exposure through a laser beam that is moved, for example, under computer control over the surface of the coated substrate and in this way forms an image, and irradiation with computer-controlled electron beams.

The photosensitivity of the compositions according to the invention generally ranges from the UV region (approx. 200 nm) to approx. 600 nm and thus spans a very wide range. A large number of different types are therefore used as light sources. Both point sources and flat spotlights (lamp carpets) are suitable. Examples are: carbon arc lamps, xenon arc lamps, mercury vapor lamps, possibly doped with metal halides (metal halogen lamps), fluorescent lamps, argon incandescent lamps, electron flash lamps, photographic floodlights, electron beams and X-rays, generated using synchrotrons or laser plasma.
The distance between the lamp and the image material according to the invention can vary, for example between 2 cm and 150 cm, depending on the application and the lamp type or intensity. Laser light sources, for example excimer lasers, such as Kripton fluoride lasers, are particularly suitable for exposure at 248 nm. The high sensitivity of the materials according to the invention is very advantageous here. This method can be used to produce printed circuits in the electronics industry, lithographic offset printing plates or relief printing plates and photographic image recording materials.

After the imagewise exposure of the material and before development, it can be advantageous to carry out a thermal treatment for a shorter time. Only the exposed parts are thermally hardened. The temperatures used are generally 50-150 ° C, preferably 80-130 ° C; the time for the thermal treatment is usually between 0.25-10 minutes.

After exposure and, if appropriate, thermal treatment, the unexposed areas of the photoresist are removed in a manner known per se using a developer.

As already mentioned, the compositions according to the invention can be developed in aqueous alkaline solution. Suitable aqueous-alkaline developer solutions are, in particular, aqueous solutions of tetraalkylammonium hydroxides or of alkali metal silicates, phosphates, hydroxides and carbonates. Smaller amounts of wetting agents and / or organic solvents can optionally be added to these solutions. Typical organic solvents that can be added to the developer liquids in small amounts are, for example, cyclohexanone, 2-ethoxyethanol, toluene, acetone and mixtures of such solvents.

The compositions according to the invention are particularly suitable for the production of printing plates, printed circuits and integrated circuits.

The following examples illustrate the invention.

Example 1: Preparation of 4-vinylbenzaldehyde.

In a 250 ml 3-necked round bottom flask with reflux condenser, mechanical stirrer, internal thermometer and nitrogen line, 18.4 g (133 mmol) 4-4 g are slowly added to a mixture of 6.5 g (268 mmol) magnesium shavings in 100 ml tetrahydrofuran (THF). Dripped chlorostyrene. The reaction mixture is kept at 50 ° C. for 1 hour and then a solution of 9.8 g (134 mmol) of dimethylformamide in 50 ml of THF is added dropwise. After 12 hours at room temperature it is poured onto ice and extracted with diethyl ether. The organic phase is washed twice with water, dried over magnesium sulfate and concentrated, 18.3 g of product being obtained as a pale yellow oil. After purification by means of column chromatography (silica gel, hexane / diethyl ether 4: 1), 12.6 g (95.3 mmol, 72% of theory) of 4-vinylbenzaldehyde are obtained.
1 H-NMR (CDCl₃, 100 mHz): δ 9.95 / s, 7.80 / d (J = 9 Hz), 7.49 / d (J = 9 Hz), 6.74 / dd (J₁ = 18 Hz, J₂ = 11 Hz), 5.87dd (J₁ = 18 Hz, J₂ = 2 Hz), 5.39 / dd (J₁ = 11 Hz, J₂ = 2 Hz).

Example 2: Preparation of 2- (4-ethenylphenyl) -1,3-dioxolane.

In a 250 ml 3-neck round bottom flask, 13.72 g (103 mmol) of 4-vinylbenzaldehyde, 7.08 g (114 mmol) of ethylene glycol and 0.23 g (1.3 mmol) of p-toluenesulfonic acid are added to 100 ml of toluene. The resulting mixture is refluxed for 3 hours under reduced pressure at 45 ° C. on a water separator. Then it is washed twice with 100 ml of water, the organic phase is over magnesium sulfate dried and concentrated to give 17.47 g of crude product as a pale yellow oil. This is distilled at 80 ° C / 0.05 mbar. Yield: 12.81 g (72.7 mmol, 70.6% of theory).
1 H-NMR (CDCl₃, 100 mHz): δ 7.39 / s / 4H, 6.68 / dd (J₁ = 11 Hz, J₂ = 18 Hz) / 1H, 5.74 / s / 1H, 5.72 ( J₁ = 18 Hz, J₂ = 2 Hz) / 1H, 5.22 / dd (J₁ = 11 Hz, J₂ = 2 Hz) / 1H, 3.96 / m / 4H.

Example 3: Preparation of 4-hydroxystyrene.

150 g (0.91 mol) of 4-hydroxycinnamic acid, 6 g (54 mmol) of hydroquinone and 6 g (39 mmol) of 1,8-diazabicyclo are added to a 1 liter sulfonation flask with mechanical stirrer, reflux condenser and nitrogen line [5.4. 0] undecen-7 with 300 ml of dimethyl sulfoxide. The mixture is then heated to 135 ° C. for 3 1/2 hours. After cooling, the mixture is poured onto ice, extracted three times with 500 ml of diethyl ether, the organic phase is washed five times with 100 ml of water, dried over magnesium sulfate and concentrated. The resulting oil is recrystallized twice from n-hexane, 69.07 g (0.58 mol, 63% of theory) of 4-hydroxystyrene being obtained as a white powder (mp. 68 ° C.).
1 H-NMR (CDCl₃, 100 mHz): δ 9.52 / s / 1H, 7.26 / d (J = 9 Hz) / 2H, 6.69 / d (J = 9 Hz) / 2H, 6.6 / dd (J₁ = 18 Hz, J₂ = 12 Hz) / 1H, 5.58 / dd (J₁ = 18 Hz, J₂ = 2 Hz) / 1H, 5.02 / dd (J₁ = 12 Hz, J₂ = 2 Hz ) / 1H.

Elemental analysis

Example 4: Preparation of 4-tetrahydropyran-2-yloxystyrene.

In a 250 ml round bottom flask, 15 g (125 mmol) of 4-hydroxystyrene and 0.4 g (2.3 mmol) of p-toluenesulfonic acid monohydrate are dissolved in 120 ml of diethyl ether. Then 11.6 g (137 mmol) of 3,4-dihydro-2H-pyran are added dropwise at 5 ° C. over a period of 10 minutes. The mixture is allowed to reach room temperature and stirring is continued for 20 hours. Then 1N NaOH solution is added, the organic phase is washed twice with water, dried over magnesium sulfate and concentrated. This results in 23.3 g (114 mmol, 90% of theory) of 4-tetrahydropyran-2-yloxystyrene as a colorless oil which is used for the copolymerization without further purification.
1 H-NMR (CDCl₃, 100 mHz): δ 7.37 / d (J = 9 Hz) / 2H, 7.02 / d (J = 9 Hz) / 2H, 6.52 / dd (J₁ = 18 Hz, J₂ = 11 Hz) / 1H, 5.50 / dd (J₁ = 18 Hz, J₂ = 2 Hz) / 1H, 5.41 / m / 1H, 5.11 / dd (J₁ = 11 Hz, J₂ = 2 Hz ) / 1H, 4.0-3.7 / m / 1H, 3.7-3.4 / m / 1H, 2.2-1.2 / m / 6H.

Elemental analysis:

Example 5: Preparation of 2- (4-ethenylphenyl) -1,3,5,5-dimethyldioxane.

In a 250 ml 3-neck round bottom flask, 65 ml of toluene with 10.0 g (75.7 mmol) of 4-vinylbenzaldehyde, 8.67 g (83 mmol) of 2,2-dimethyl-1,3-propanediol and 0.15 g (0.9 mmol) of p-toluenesulfonic acid were added. The mixture is refluxed for 5 hours on a water separator and then mixed with 50 ml of 0.1 N sodium hydroxide solution. The organic phase is separated off, washed three times with water, dried over magnesium sulfate and concentrated. The resulting crude product is recrystallized from methanol / water. Yield: 10.9 g (45.8 mmol; 60.5% of theory) in the form of white crystals. Melting purple: 45-46 ° C.
1 H-NMR (CDCl₃, 100 MHz): δ 7.46 / d / 2H, 7.39 / d / 2H, 6.71 / dd / 1H, 5.75 / d / 1H, 5.38 / s / 1H , 5.24 / d / 1H, 3.77 / d / 2H, 3.64 / d / 2H, 1.29 / s / 3H, 0.80 / s / 3H.

Example 6: Preparation of 4-ethenylphenyl-di-n-propoxymethane.

6.8 g (51.5 mmol) of 4-vinylbenzaldehyde, 12.4 g (205.8 mmol) of n-propanol and 0.1 g (0.5 mmol) of p-toluenesulfonic acid are dissolved in a 100 ml 3-neck round bottom flask 45 ml of benzene dissolved. The solution is refluxed on the water separator for 22 hours and then mixed with ether. It is then neutralized with 0.1 N sodium hydroxide solution. The organic phase is then washed three times with water, dried over magnesium sulfate and concentrated. The resulting oil can be purified by column chromatography (static phase silica gel, mobile phase hexane-ether 5/4), 2.54 g (10.8 mmol, 21% of theory) of the desired substance being obtained as a clear oil.
1 H-NMR (CDCl₃, 100 MHz): δ 7.41 / m / 4H, 6.71 / dd / 1H, 5.89 / d / 1H, 5.50 / s / 1H, 5.23 / d / 1H , 3.46 / m / 4H, 1.62 / m / 4H, 0.94 / t / 6H.

Example 7: Copolymerization of 4-hydroxystyrene and 2- (4-ethenylphenyl) -1,3-dioxolane.

1.8 g (10 mmol) of 2- (4-ethenylphenyl) -1,3-dioxolane and 2.4 g (20 mmol) of 4-hydroxystyrene are freshly distilled with 0.1 g of α, α'-azoisobutyronitrile in 17 g Radically copolymerized THF at 70 ° C for 24 hours. After two precipitations from 400 ml of n-hexane, the product is isolated as a white powder; Yield 2.5 g (60% of theory).
1 H-NMR (DMSO, 300 mHz): δ 8.9 / s, 7.3-6.9 / m, 6.8-6.0 / m, 5.7-5.5 / m, 4.1 -3.8 / m, 2.0-0.9 / m.
Installation ratio 4-hydroxystyrene / 2- (4-ethenylphenyl) - 1,3-dioxolane = 1: 1 (1 H-NMR). The following are determined by gel permeation chromatography (GPC, polystyrene calibration): Mn = 4870, Mw = 12410, Mw / Mn = 2.5.
Tg = 84 ° C, determined by differential scanning calorimetry, DSC (10 ° / min).

Example 8: Copolymerization of 4-hydroxystyrene and 2- (4-ethenylphenyl) -1,3-dioxolane.

1.8 g (10 mmol) of 2- (4-ethenylphenyl) -1,3-dioxolane and 6.0 g (50 mmol) of 4-hydroxystyrene are freshly distilled with 0.23 g of α, α'-azobisisobutyronitrile in 31 g THF copolymerized at 70 ° C for 24 hours. The copolymer is isolated as a white powder by precipitation twice from 600 ml of n-hexane; Yield 5.0 g (64% of theory).
1 H-NMR (CDCl₃, 300 MHz): δ 8.4 / s, 7.3-6.9 / m, 6.9-6.1 / m, 5.8-5.7 / m, 4.1 -3.9 / m, 2.0-0.9 / m.
Installation ratio 4-hydroxystyrene / 2- (4-ethenylphenyl) -1,3-dioxolane = 4: 1 (1 H-NMR).
GPC (polystyrene calibration): Mn = 2260, Mw = 9160, Mw / Mn = 4.2.

Example 9: Copolymerization of 4-tetrahydropyran-2-yloxystyrene with 2- (4-ethenyl) -1,3-dioxolane.

6.1 g (30 mmol) of 4-tetrahydropyran-α-yloxystyrene and 1.8 g (10 mmol) of 2- (4-ethenyl) - 1,3-dioxolane are mixed in with 0.18 g of α, α′-azoisobutyronitrile 32 g of toluene copolymerized at 70 ° C for 24 hours. After two precipitates in methanol, 4.9 g (62% of theory) of the copolymer are obtained in the form of a white powder.
1 H-NMR (CDCl₃, 300 MHz): δ 7.4-6.1 / m, 5.8-5.6 / bs, 5.2-5.5 / bs, 4.2-3.8 / m , 3.7-3.4 / bs, 2.2-1.0 / m.
Installation ratio 4-tetrahydropyran-2-yloxystyrene / 2- (4-ethenylphenyl) -1,3-dioxolane = 2: 1 (1 H-NMR).
GPC: Mn = 6210, Mw = 14730, Mw / Mn = 2.4.

The phenol in the structural elements from 4-tetrahydropyran-2-yloxystyrene is released by stirring for 60 minutes in tetrahydrofuran under an inert gas atmosphere in the presence of a catalytic amount of acetic acid at room temperature.

Example 10: Copolymerization of 4-hydroxystyrene and 4-ethenylphenyl-di-n-propoxymethane.

In a 100 ml round bottom flask, 2.34 g (10 mmol) of 4-ethenylphenyl-di-n-propoxymethane, 6.0 g (50 mmol) of 4-hydroxystyrene and 0.25 g of α, α'-azoisobutyronitrile in 33 g of tetrahydrofuran solved. The mixture is refluxed for 24 hours and then precipitated in 10 times the amount of n-hexane. This results in 6.12 g (73% of theory) of a white powder.
GPC (polystyrene calibration): Mn = 2860, Mw = 12940, Mw / Mn = 4.5.
DSC (10 ° / min): Tg = 51 ° C.

Example 11: Copolymerization of 4-hydroxystyrene with 4- (2-ethenylphenyl-1,3,5,5-dimethyldioxane.

2.18 g (10 mmol) of 4- (2-ethenylphenyl-1,3,5,5-dimethyldioxane, 6.0 g (50 mmol) of 4-hydroxystyrene and 0.25 g of α, α '-Azoisobutyronitrile dissolved in 32 g tetrahydrofuran After 24 hours of refluxing, is precipitated from n-hexane, the resulting white powder is dissolved in tetrahydrofuran and again precipitated from ten times the amount of n-hexane, 5.5 g (67% of theory Th) of a white powder result.
GPC (polystyrene calibration): Mn = 5480, Mw = 13410, Mw / Mn = 2.4.
DSC (10 ° / min): Tg = 53 ° C.
1 H-NMR (acetone-d₆, 100 MHz): 6 8.0, 7.3, 6.6, 5.4, 3.7, 2.1-1.1, 1.3.
Installation ratio 4- (2-ethenylphenyl) -1,3,5,5-dimethyldioxane / 4-hydroxystyrene = 1: 3 (determined by 1 H-NMR spectroscopy).

Example 12:

A resist mixture is provided by dissolving 90 parts by weight of the copolymer according to Example 7 and 10 parts by weight of triphenylsulfonium trifluoromethanesulfonate in 350 parts by weight of cyclopentanone. This mixture is spun onto a silicon wafer and dried at 120 ° C. for 2 minutes. The result is a resist film with a layer thickness of 1.0 µm, which is then exposed imagewise through a quartz mask. A mercury vapor lamp is used as the light source and remains on for 3 seconds. After the exposure, the mixture is heated to 90 ° C. for 3 minutes and then developed in a solution of 15% by weight of tetramethylammonium hydroxide in water. The exposed areas of the film remain as relief structures of the original thickness, while the unexposed areas are resolved. The resist material obtained allows the resolution of submicron structures.

Example 13:

A resist solution is provided by dissolving 96 parts by weight of the copolymer according to Example 8 and 5 parts by weight of triphenylsulfonium trifluoromethanesulfonate in 250 parts by weight of cyclohexanone. The solution is spun onto a silicon wafer and then dried at 120 ° C. for 2 minutes. whereby a resist film with a thickness of 1.1 μm is obtained. The optical density of this film, measured on a quartz disc, has a value of 0.32 at 248 nm. The one with the resist film. coated wafers are now exposed through a quartz mask with interference narrow-band filter at 254 nm and a dose of 20 mJ / cm² and then heated to 120 ° C. for 1 min. In the subsequent development in a 2.38% by weight aqueous solution of tetramethylammonium hydroxide, the exposed areas of the film remain as relief structures of the original thickness, while the unexposed areas are dissolved. With a contrast value y of 3.0, the resist material obtained is able to reproduce structures up to 0.5 microns l / s (lines and spaces) true to line and without swelling.

Example 14:

The resist solution obtained according to Example 11 is applied to a copper-clad printed circuit board by brushing and dried in a heating cabinet at 100 ° C. for 15 minutes, resulting in resist films with a layer thickness of 15 μm. The mask is then exposed to a mercury vapor pressure lamp for 15 seconds and the plate is then kept at 120 ° C. for 2 minutes. The mixture is then developed in a 2.38% by weight solution of tetramethylammonium hydroxide in water for 1 minute, the exposed areas of the resist film remaining behind and the unexposed areas being dissolved.

Claims (17)

Acid-catalytically crosslinkable copolymer with a molecular weight (Mw) of 10³ to 10⁶, measured by means of gel permeation chromatography a) 100-80 mol.% of recurring structural elements of the formulas I and II

in the ratio of 1: 1 to 1: 9 and b) 0-20 mol% of recurring structural elements of the formula III

consists in what
X and X 'independently of each other

mean, R is hydrogen or a protective group which can be split off under the action of acid, which R₁ independently of one another is C₁-C₅-alkyl, phenyl or naphthyl or together 1,2-phenylene or - [C (R₃) (R₄)] _x - with R₃ and / or R₄ = Represent hydrogen or methyl and x = 2 to 5,
the R₂ are independently hydrogen, C₁-C₅-alkyl or C₁-C₅-alkoxy,
R₅ and R₇ are each hydrogen,
R₆ is hydrogen, halogen or methyl and
R₈ is hydrogen, halogen, methyl, -CH₂Halogen, -CH₂CN, -CN, -COOH, -CONH₂, -O-C₁-C₅-alkyl, -O-CO-C₁-C₅-alkyl, -COO-C₁-C₅-alkyl , -COO-phenyl or phenyl mean,
or R₅ and R₆ are each hydrogen and R₇ and R₈ together are -CO-O-CO- or independently of one another -COOH or -COO-C₁-C₅-alkyl. Copolymer according to Claim 1, which consists of 100-90 mol% of recurring structural elements of the formulas I and II and of 0-10 mol% of recurring structural elements of the formula III. A copolymer according to claim 1, wherein X and X ′

and especially ever

represent. A copolymer according to claim 1, wherein the R₁ together - [C (R₃) (R₄)] _x - and R₂ each represent hydrogen, methyl, ethyl, methoxy or ethoxy. A copolymer according to claim 1, wherein R is a radical of the formulas IV, V, VI or VII

-CO-R₁₃ (VII), wherein
R₉ is hydrogen or methyl,
R₁₀ is C₁-C₅-alkyl, phenyl or naphthyl and R₁₁ and R₁₂ are independently hydrogen, C₁-C₅-alkyl, phenyl or naphthyl, or
R₁₀ and R₁₂ together represent unsubstituted or substituted by C₁-C₄-alkyl, C₁-C₄-alkoxy, phenyl, naphthyl, phenoxy or naphthyloxy, ethylene, propylene or butylene,
y represents 2, 3 or 4, and
R₁₃ is C₁-C₅ alkyl or C₁-C₅ alkoxy. A copolymer according to claim 5, wherein R represents -COO-C (CH₃) ₃ and in particular a radical of formula V with y = 2 or 3. A copolymer according to claim 1, wherein X and X ′

R and the two R₂ each hydrogen and the R₁ together - [C (R₃) (R₄)] _x - with x = 2 to 4, especially 2 or 3, mean. Containing radiation sensitive composition i) at least one copolymer according to claim 1 and ii) at least one acid-forming compound under actinic radiation. A composition according to claim 8, containing as further component iii) a solvent or a solvent mixture. A composition according to claim 8, wherein the copolymer i) consists of 100-90 mol% of recurring structural elements of the formulas I and II and 0-10 mol% of recurring structural elements of the formula III. A composition according to claim 8, wherein X and X ′ in the copolymer i)

and especially ever

represent. A composition according to claim 8, wherein R in the copolymer i) -COO-C (CH₃) ₃ and in particular represents a radical of formula V with y = 2 or 3. A composition according to claim 8, wherein in the copolymer i) X and X ′

R and the two R₂ each hydrogen and the R₁ together - [C (R₃) (R₄)] _x - with x = 2 to 4, especially 2 or 3, mean. A composition according to claim 8, containing as component ii) at least one compound of formula VIII $${\text{(Ar₁)}}_{\text{q}}{\text{(Z₁)}}_{\text{r}}{\text{(Z₂)}}_{\text{s}}{\text{S}}^{\text{⊕}}{\text{X₁}}^{\text{⊖}}$$

wherein
Ar₁ is phenyl, naphthyl or phenyl-COCH₂- which is unsubstituted or substituted by halogen, C₁-C₄-alkyl, C₁-C₄-alkoxy, -OH and / or nitro,
Z₁ C₁-C₆-alkyl or C₃-C₇-cycloalkyl and
Z₂ are tetrahydrothienyl, tetrahydrofuryl or hexahydropyryl,
q for 0, 1, 2 or 3,
r for 0, 1 or 2 and
s stand for 0 or 1, the sum q + r + s being 3, and
X₁ ^{⊖ is} a chloride, bromide or iodide anion, BF₄ ^⊖ , PF₆ ^⊖ , AsF₆ ^⊖ , SbF₆ ^⊖ , FSO ^⊖ or the anion of an organic sulfonic acid or carboxylic acid. The composition of claim 14 wherein Ar₁ is phenyl, q is 3, r and s are zero, and X₁ ^⊖ SbF₆ ^⊖ , AsF₆ ^⊖ , PF₆ ^⊖ , CF₃SO₃ ^⊖ , C₂F₅SO₃ ^⊖ , n-C₃F₇SO₃ ^⊖ , n-C₄F₉SO₃ ^⊖ , n-C₆F₁₃SO₃ ^⊖ , n-C₈F₁₇SO₃ ^⊖ or C₆F₅SO₃ ^⊖ . A composition according to claim 8, wherein the compound ii) is present in an amount of 0.1 to 20% by weight, especially 1 to 10% by weight, based on the weight of the copolymer i). Use of radiation-sensitive compositions according to claim 8 for the production of protective layers and relief structures, in particular for the production of printing plates, printed circuits and integrated circuits.